Replaceable insert for tuyere pipes of metal-refining furnaces

ABSTRACT

An assembly of insert piping for a tuyere pipe of a metal refining furnace comprises a length of pipe flared outwardly at one end to approximately the internal diameter of the tuyere pipe of the furnace, so as to fit snugly therein. The length of pipe is provided at its flared end with means for connection with a pipe puller and has its other end provided with means for temporary connection with a length of injection pipe that is adapted to project several inches into the furnace. The flared end of the flared pipe is preferably a bell-end adapter pipe fitting into which a pipe puller can be screwed, and the opposite end of such flared pipe is preferably connected to the injection pipe by means of a sleeve pipe coupling. The flared length of pipe is preferably of black iron perforated along its length to permit gas circulation therearound.

United States Patent [1 1 3,695,603 Walk et al. [451 Oct. 3, 1972 [54] REPLACEABLE INSERT FOR TUYERE 2,261,559 11/1941 Osborn ..266/41 PIPES OF METAL-REFINING 1,229,938 6/1917 Golden ..266/41 FURNACES Pr E G aldA D0 imary xaminer er st [72] Inventors George walk h Jones Attorney-John L. Sniado, Mallinckrodt and Cornaby Salt Lake Utah and Philip A. Mallinckrodt [73] Assignee: Kennecott Copper Corporation,

New York, N.Y. ABSTRACT 22 Filed; Sept 22 1970 An assembly of insert piping for a tuyere pipe of a metal refining furnace comprises a length of pipe [21] PP 74,283 flared outwardly at one end to approximately the internal diameter of the tuyere pipe of the furnace, so as 52 Us. Cl ..266/41 to fit snugly thereih- The length of P is Provided at 51 Int. Cl ..F27k 5/16 its flared end with means Connection with a P [58] Field of Search ..75/72-76 and has its other end Pmvided with means for 110/1325. 122/66. 266/41 temporary connection with a length of injection pipe that is adapted to project several inches into the furnace. The flared end of the flared pipe is preferably a [56] References cued bell-end adapter pipe fitting into which a pipe puller UNITED STATES PATENTS can be screwed, and the opposite end of such flared pipe is preferably connected to the injection pipe by 2,480,394 8/1949 Cavers et a1. means of a sleeve p p coupling The flared length of 3,088,725 5/1963 l-lall ..266/41 p is preferably of black iron perforated along its 95,661 10/ 1869 Davidson ..l22/6.6 length to permit gas circulation therearound' 1,729,447 9/1929 McKee ..l10/182.5

235,391 12/1880 Stoll ..110/182.5 3 Claims, 4 Drawing Figures REPLACEABLE INSERT FOR TUYERE PIPES OF METAL-REFINING FURNACES BACKGROUND OF THE INVENTION Field: The invention relates to tuyere pipe inserts for introducing gas into metal refining furnaces through the tuyere pipes that are normally provided in such furnaces.

State of the Art: Gas has heretofore been introduced into molten metal in metal-refining furnaces, particularly molten copper in furnaces used for the pyrometallurgical refining of anode copper, through insert pipes driven into tuyere pipes inserted in the furnace walls. An insert pipe is normally of stainless steel, with one end notched and bent outwardly so it can be wedged tightly against the interior walls of the tuyere pipe to hold such insert pipe in place. The opposite end of the insert pipe extends several inches into the interior of the furnace and burns off over a period of time. As the inner projecting end of the insert pipe is burned off, it is common practice to drive such insert pipe farther down the tuyere pipe with a sledge hammer. Often the pipe becomes plugged by this rough treatment and must be driven entirely into the furnace so it can be replaced. Costs of labor and of replacements for the insert pipes are not insignificant.

Object: A principal object in the making of this invention was to provide a tuyere pipe insert which is withdrawable from the tuyere pipe when the insert becomes too short for continued use and which can be easily replaced with a new insert.

SUMMARY OF THE INVENTION According to the invention, the tuyere pipe insert is a piping assembly comprising a length of preferably inexpensive black iron pipe flanged at one end, advantageously by thrcadedly attaching thereto a bell-end adapter pipe fitting. The assembly further comprises a second length of pipe removably attached, as by means of a standard sleeve coupling, to the other end of the first length of pipe. The second length of pipe is preferably of stainless steel for extending into the furnace in the usual manner. When the projecting end of the insert pipe has been burned off the entire insert assembly is easily withdrawn from the tuyere pipe by connecting a pipe puller to the flanged end. Thereupon, a longer piece of flanged pipe is attached to the remaining length of insert pipe, and the insert assembly is replaced in the tuyere pipe so that the insert pipe again projects the required distance within the furnace. In this way the entire insert pipe can be used. Its progressive projection into the furnace is accomplished easily and without danger of plugging the pipe.

As is customary, the tuyere pipe includes a T pipe fitting at its outer end that provides an opening for connection with a gas'supply conduit. The other opening that is normally plugged now affords access for a pipe puller when required. Ordinarily it remains closed by the usual pipe plug.

The flanged pipe is preferably perforated along its length, thereby permitting a portion of any gas flowing therethrough to escape through the perforations and into the annular space between the insert and the tuyere pipe for cooling purposes.

THE DRAWING The best mode presently contemplated of carrying out the invention is illustrated in the accompanying drawing, in which:

FIG. 1 is a fragmentary view in horizontal section taken through a wall of a typical copper anode furnace along the longitudinal axis of a tuyere pipe in which is installed a tuyere pipe insert assembly of the invention;

FIG. 2, a longitudinal axial section showing the tuyere pipe insert of FIG. 1 per se, the view being drawn to a larger scale and intermediate portions being broken out for convenience of illustration;

FIG. 3, that portion of FIG. 1 enclosed by the broken line 3; and

FIG. 4, a view corresponding to that of FIG. 3, but showing a pipe puller in the act of removing the tuyere pipe insert from the tuyere pipe.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT In the illustrated form of the invention, a tuyere pipe insert assembly 10 is disposed concentrically within a standard tuyere pipe 11 of a copper anode metallurgical furnace 12. Tuyere pipe 1 1 extends entirely through a refractory-lined side wall 12a of such furnace to the interior 12b of the furnace, and as usual, comprises a black iron pipe 11a within which is snugly fitted a stainless steel pipe llb that projects a limited distance exteriorly of the furnace sufficient to receive a standard pipe bushing 13 and the usual T pipe fitting 14. A gas line 15 is connected in customary manner to the branch opening 14a of the T and the usual pipe plug 16 normally closes the other open end of the through passage 14b of the T. I

The insert assembly 10 comprises a length of pipe 17 having its outer end 17a flared outwardly by threaded connection to the small end 18a of a bell-end adapter pipe fitting 18. The large end 18b of such pipe fitting 18 is internally threaded, as at 19, to receive and securely engage a pipe puller 20, FIG. 4, when it is desired to remove insert assembly 10 from tuyere pipe 11. Removably connected to the other end of pipe length 17 is a second length of pipe 21 serving as an injection pipe and adapted to extend to and project several inches within the interior 12b of furnace 12 as at 21a. A pipe sleeve 22 serves as the means of interconnecting mutually adjacent, threaded end 17b and 21b of pipes 17 and 21, respectively.

It is preferred that pipe 17 be of black iron, perforated as at 23 for cooling purposes, and that injection pipe 21 be of stainless steel as is customary for gas-injection insert pipes in metallurgical furnace tuyere pipes.

Bell-end adapter pipe fitting 18 fits within bushing 13 in abutting relationship with the adjacent end of insert pipe 17, see FIG. 3, thereby supporting insert piping assembly 10 concentrically within the tuyere pipe. Opening 14b of T pipe fitting 14 is in axial alignment with the component tuyere pipes and 11b. When the end 21a of insert pipe 21 has burned off, pipe plug 16 can be easily removed and pipe puller 20 inserted therethrough so its threaded end 20a can be screwed into the threads 19 of bell-end adapter fitting l8 and the entire insert pipe assembly 10 pulled free of tuyere pipe 11.

Following removal of the insert pipe assembly, it is disassembled by unscrewing bell-end adapter fitting l8 and the entire insert pipe assembly 10 pulled free of tuyere pipe 11.

Following removal of the insert pipe assembly, it is disassembled by unscrewing bell-end adapter fitting l8 and pipe sleeve 22 from the ends of pipe 17. Pipe 17 then is replaced by a similar pipe sufiiciently longer than the one it replaces to position the shortened injection pipe 21 as it was originally so far as projection of its inner end into the interior 12b of the furnace is concerned.

The re-assembled insert pipe assembly is then replaced in tuyere pipe 11 by use of pipe puller 20, now serving as a pipe pusher.

Whereas this invention is here illustrated and described with respect to a certain preferred form thereof, it is to be understood that many variations are possible without departing from the inventive concepts particularly pointed out in the claims.

We claim:

1. In combination with a metal-refining furnace having a tuyere pipe which includes pipe means extending through a wall of the furnace and a T pipe fitting having one open end of its through passage attached to the outer end of said pipe means, an insert assembly for said tuyere pipe comprising a length of pipe having one end threaded into a bell-end adapter pipe fitting, the

outwardly flared bell' end of said adapter pipe fitting being internally threaded to provide for connection with a pipe puller; means at the other end of said length of pipe providing connection for a length of injection pipe; and a length of injection pipe connection to said other end of the first length of pipe so as to be replaceable; said assembly being fitted into said tuyere pipe with the said bell-end adapter pipe fitting within said T pipe fitting and abutting against said pipe means; the injection end of said length of injection pipe projecting within the furnace and normally remaining stationary therein during operation of the furnace; a pipe plug normally closing the opposite, open end of the through passage of said T fitting in substantially axial alignment with said pipe means, whereby removal of said plug enables use of a pipe puller to remove said insert assembly; and a pipe line for the supply of a combustion supporting gas connected to the branch opening of said T pipe fitting.

2. A combination in accordance with claim 1, wherein the connecting ends of the first length of pipe and of the length of injection pipe, respectively, are externally threaded, and the connection means is a pipe sleeve threaded onto the said connecting ends.

3. A combination in accordance with claim 1, wherein the first length of pipe is perforated to provide gas circulation therearound for cooling purposes. 

1. In combination with a metal-refining furnace having a tuyere pipe which includes pipe means extending through a wall of the furnace and a T pipe fitting having one open end of its through passage attached to the outer end of said pipe means, an insert assembly for said tuyere pipe comprising a length of pipe having one end threaded into a bell-end adapter pipe fitting, the outwardly flared bell end of said adapter pipe fitting being internally threaded to provide for connection with a pipe puller; means at the other end of said length of pipe providing connection for a length of injection pipe; and a length of injection pipe connection to said other end of the first length of pipe so as to be replaceable; said assembly being fitted into said tuyere pipe with the said bell-end adapter pipe fitting within said T pipe fitting and abutting against said pipe means; the injection end of said length of injection pipe projecting within the furnace and normally remaining stationary therein during operation of the furnace; a pipe plug normally closing the opposite, open end of the through passage of said T fitting in substantially axial alignment with said pipe means, whereby removal of said plug enables use of a pipe puller to remove said insert assembly; and a pipe line for the supply of a combustion supporting gas connected to the branch opening of said T pipe fitting.
 2. A combination in accordance with claim 1, wherein the connecting ends of the first length of pipe and of the length of injection pipe, respectively, are externally threaded, and the connection means is a pipe sleeve threaded onto the said connecting ends.
 3. A combination in accordance with claim 1, wherein the first length of pipe is perforated to provide gas circulation therearound for cooling purposes. 